Heating system



LIE MAcDONAL'D HEATI NG SYSTEM. APPLICATION, man MARJH, 1915.

,fiflfi fig k Patentad- Jan. 6, 1926.

y iwggcfc w, 17am,

Fli ht @TATEtt rarnu'r OFFICE.

JOHN E. MAcT-ONALD, RIVER FOREST, ILLINOIS, ASSIGNOR TO ILLINOIS-ENGINEER- ING- COMPANY, OF CHICAGO, ILLINDIS, A CORPORATION OF ILLINOIS.

HEATING SYSTEM.

Specification of Letters Patent.

Patented J an. 6, 1920.

Application filed March 11, 1915; Serial No. 13,765.

State of Illin0is,'have invented certain new and useful Improvements in Heating Systems, of which the following is a specification.

This invention relates to heating systems, and more particularly to apparatus capable of use in systems of the low pressure vacuum type, though its application is not necessarily confined to such use.

The salient objects of the invention are to provide in a system or apparatus. of the character referred to, means for effectively returning the water of condensation to the boiler and to insure the passage of the water of mndensatiou into the return tank at all timesduring the operation ofthe system; to provide a construction in which the passage of steam up through the main water of condensation pi e is prevented by a check or other suitable valve; to avoid danger of the check valve em )lOVGd in' the return i e being locked by i us of a vacuum created on the opposite s s of the valve from the return tank; to proude means for permitting the escape Of air from the system Without allowing ingress of air; to provide an automatically operated valve for closing communication between the return tank and the air ventduring the period when steam is being admitted to the return tank; to

mount the valve which controls the air vent and the valve which controls the admission or steam to the return tank that they will be alternately opened and closed by a float-actuated mechanism; to so mount the valves that they can'be easily opened and closed, one oi. said valves being closed whenever the other is ope and in genc {ii to provide an iniproveo apparatus of the character re ferred to.

In the drawings-- Figure 1 is a fragmentary side elevation showing a heating unit, return tank and the connection therebctween;

Fig. 2- is a fragmentary cross-section through. the valve mechanism.

Referring to the neral arrangement of the apparatus as shown in Fig. 1, 1 designates the boiler and it the heating unit connected to the boiler in the usual manner by means of a main steam pipe 3 and an up-- 1ighl3 4.. The opposite end of the heating unit is connected to a return pipe 5 through which the water of condensation passes to the main water of condensation pipe 6. This latter pipe 6 discharges into a return pipe 8 leading back to the boiler.

In systems of the low pressure vacuum type, it is necessarythat the water of con densation in the return tank 7 be put under suflicient pressure to cause it to return tothe boiler, and in the present construction it is accomplished by means of a pipe 9 leading from the main steam pipe 3 to the return tank 7. Communication between the pipe 9 and the return tank 7 is controlled by means of an automatically operated valve 10, the mechanism for operating which is hereinafter described in detail. In order that any air-getting into the system may be discharged, 1 preferably employ an air vent 11 leading from the main water of condensation pipe 6, the lower end of this air vent being provided with a mercury seal 12, which will allow the escape of air, but will prevent the ingress of air into the system.

A second; air vent 13 is also employed, this air vent also being provided with a mercury-seal 14. The second air seal may in some cases be dispensed with but I have found in practice that the apparatus operates more satisfactorily with two air seals. The air vent 13 has a direct connection with the return tank 7 by means of a pipe 15, communication between this pipe and the return tank being controlled by means of an automatically operated valve16. As shown in detail in Fig. 2, the valves and 16 are carried at opposite ends of-a lever 17 This lever 17 is fulcrumed at 18'so as to seat one valve whenever the lever 17 rocks to open-the other valve. /Vhile various constructions be employed for rocking this lever, the particular means shown comprises a floatlever 19 pivoted to the return tank at 20 and having its opposite end provided with a float 21. The levers 17 and 19 are connected to each otherby means of a link 22- The operation of the valve-controlling H h the pipe 15 and the air vent is discharged from the latter through the mercury seal 14. As the water of condensation accumulates in the return tank 7, it

level of the water of condensation in the return tank 7 lowers, the float 21 will also lower, and the proportioningof the parts is suchthat the lever 19 will by gravity rock downward and automatically seat the valve 10 and unseat the valve 16.

During the period when the contents of the return tank 7 are under pressure, it is desirable to guard against the steam passing into the main water of condensation pipe 6. In the construction shown in the drawings, I employ for this purpose a check valve 23 opening toward the return tank from its position in the main water of condensation pipe 6. Thus the water of condensation is free to pass toward the return tank, but the passage of steam from the latter is prevented automatically by the check valve 23. At

certain times, particularly when the heating system is being started, thereis a tendency to form a vacuum, or at least a lesser pressure on the side of the check valve which is farthest from the return tank. This interferes with the normal operation of the system, since it tends to draw the'check valve against its seat and to prevent the passage of the water of condensation into the return tank. I have guarded against the locking of the check valve 23 by the following novel arrangement of parts:

Leading from the pipe 15 is a connection 24 in open communication with the main water of condensation pipe 6. As the valve 16 is normally unseated, there is an effective by-pass from the return tank to the main pipe 6 around the check valve 23. Thus the air pressure on opposite sides of the valve 23 will be automatically balanced, and the formation of an unequal pressure is prevented. Moreover, since the p1pe 15 is controlled by the automatically operated valve 16, there is can be made without departing from the scope of my invention, and I do not desire to limit the latter except as specified in the ap pended claim.

I claim as my invention:

In an apparatus for use with low pressure vacuum heating systems, the combination with a boiler and a heating unit, live steam connections from the boiler to one end of the heating unit, exha 1st steam connections from the other end of the heating unit to the boiler, said connections extending above the boiler so that the condensed steam will return to the latter by gravity, a return tank interposed in said exhaust steam connections, a pipe for admitting live steam into said tank, a valve controlling the admission of steam from the pipe, an air vent leading from said tank, a second valve for controlling communication between the tank and air vent, float operated leverage mechanism for moving one of said valves into closed position and simultaneously opening the other of said valves, a check valve interposed in the exhaust steam connections between the" heating unit and return tank, connections between the air ventand that side of the check valve remote from the return tank, and an air seal connected to said air vent. JOHN E. MAoDONALD. lVitnesses:

J OYGE M.'LUTZ, C. B. BELKNAP. 

